JPH07309757A - Beta-amyloid protein neurocyte toxicity reducing agent - Google Patents

Abstract

PURPOSE:To obtain a therapeutic agent for Alzheimer's disease, comprising an N-(5-nitro-2-thiazolyl)benzenesulfonamide derivative as an active ingredient. CONSTITUTION:This therapeutic agent comprises a compound of the formula (R is H, a halogen, nitro, a lower alkyl or a lower alkoxy) as an active ingredient. The compound of formula I is useful as a medicine for preventing progress of dementia following Alzheimer's disease due to suppression of change and removal of neurocyte by reducing neurocyte toxicity induced by beta-amyloid protein as a main component of senile plaque accumulated in a brain of Alzheimer's disease. Part of the compound of formula I is a new compound and is obtained by reacting a 5-nitro-2-aminothiazole of formula II with a sulfonyl compound of formula III (X is reacted with amino and eliminated) in the presence of a base in a solvent. A dose is 10-100mg/kg per adult daily.

Description

Detailed Description of the Invention

[0001]

The present invention relates to N- (5-nitro-2
The present invention relates to a therapeutic agent for Alzheimer's disease containing a thiazolyl) benzenesulfonamide derivative as an active ingredient.

[0002]

2. Description of the Related Art As pathological features of Alzheimer's disease, senile plaque and PHF (paired helical fibrous).
Lament) is accumulated in the brain. Β-amyloid protein, which is the main component of senile plaque, is an insoluble peptide with about 40 residues, and it has recently been revealed that β-amyloid protein itself biochemically damages nerve cells. In 1989, neuronal toxicity of β-amyloid protein was reported in rat hippocampal neurons (Yankne.
r, B. A. Et al .: Science, Volume 250, 279-
282, 1990). On the other hand, it has been reported that β-amyloid protein enhances neuronal cytotoxicity due to glutamate through both N-methyl-D-aspartate (NMDA) and non-NMDA pathways (Koh,
J. Et al .: Brain. Res. , 533, 315-3
P. 20, 1990).

[0003] Since then, many researchers have made many discussions on the neurocytotoxicity of β-amyloid protein itself (Cotman, CW et al .: Neurobio).
l. Aging, Vol. 13, pp. 587-590, 1992.
May, P .; C. Et al .: Neurobiol. Agi
ng, Vol. 13, 605-608, 1992 etc.). As a result, it has been clarified that the neuronal cytotoxicity of the β-amyloid protein itself is biochemically caused by the aggregated β-amyloid protein, not by the solubilized β-amyloid protein (Pike, CJ. Et al: Brai
n. Res. , 563, pp. 311-314, 1991.
Year and Pike, C .; J. Et al: Eur. J. Pharm
al. , 207, pp. 367-368, 1991).
This result was retested by some subsequent reports,
Has been established (Mattson, MP et al: Bra.
in. Res. , 621, 1993, Buscig
lio, J .; Et al .: Neurobiol. Aging, 1
3, 609-612, 1992 etc.).

In addition, the aggregated β-amyloid protein causes abnormal fibers found in Alzheimer's disease (Pike, CJ, et al .: Neurorepor).
t, 3, p. 769-772, 1992) and phosphorylation of tau protein, which is a constituent of PHF (Takas).
Hima, A .; Et al: Proc. Natl. Acad. S
ci. USA, 90, 7789-7793, 199.
3 years), it has also been suggested that neuronal death is caused (Pike, CJ, et al .: Neurorepor).
t, vol. 3, pp. 769-772, 1992, Takas.
Hima, A .; Et al: Proc. Natl. Acad. S
ci. USA, 90, 7789-7793, 199.
3 years etc.).

Furthermore, in vivo,
When β protein or senile plaque core isolated from the brain of Alzheimer's disease is administered to rat cerebral cortex or hippocampus, Alz50 (antibody which recognizes phosphorylated tau) positive product appears and neuron loss occurs. Have been reported by several groups (Frautsc
hy, S.H. A. Et al: Proc. Natl. Acad. S
ci. USA, 88, 8362-8366, 199.
1 year, Kowall, N .; W. Et al: Proc. Nat
l. Acad. Sci. USA, Volume 88, 7247-7
251 p. 1991, Emre, M .; Et al: Neuro
biol. Aging, vol. 13, p. 553-560, 1
992).

Substance P has been reported as a drug for reducing the neurocytotoxicity of β-amyloid protein (Y
ankner, B. A. Et al .: Science, 250
Vol., 1990). In addition, b which is a fibroblast growth factor
It has been reported that FGF also has an action of reducing the neurocytotoxicity of β-amyloid protein (Mattson,
M. P. Et al .: Brain. Research, 621
Vol., Pp. 35-49, 1993). Furthermore, it has been reported that insulin and forskolin also have a neurocytotoxicity reducing action (Takadera, T. et al .:
Neuroscience. Letters, 161
Vol. 41-44, 1993). However, the truth is that the truth is not clear in any case.

Conventional formula

[Chemical 2] It is known that an N- (5-nitro-2-thiazolyl) benzenesulfonamide compound represented by the formula (A represents a methyl or acetamide group) has an antibacterial action or an antidiabetic action (Czechoslovakia). Patent 11
0,963).

Also, the formula

[Chemical 3] It has been reported that 4-amino-N- (5-nitro-2-thiazolyl) benzenesulfonamide represented by the formula [4] has an antibacterial action [Depeshko, I. et al. R: Far
m. Zh. , (Keiv) 5, pp. 42-45, 197.
9 years].

Furthermore, the formula

[Chemical 4] It has been reported that 4-fluoroacetamide-N- (5-nitro-2-thiazolyl) benzenesulfonamide represented by the formula has an anti-schistosomiasis action. (Che
n, Shicong. Et al: Yaoxue Xueba
o. , 17 (9), pp. 674-681, 1982.
Year).

[0010]

SUMMARY OF THE INVENTION It is desired to develop a more effective drug as a preventive or therapeutic agent for the progression of Alzheimer-type senile dementia by suppressing neuronal cell death by β-amyloid protein.

[0011]

[Means for Solving the Problems] The present inventors have conducted various searches for low-molecular-weight compounds having an action of reducing neuronal toxicity induced by β-amyloid protein and capable of penetrating the cerebral blood flow barrier. As a result, the 4-substituted-N- (5-nitro-2-thiazolyl) benzenesulfonamide compound represented by the following general formula (1) has an action of reducing neuronal cytotoxicity induced by β-amyloid protein. The present invention has been completed and the present invention has been completed.

That is, the present invention relates to the general formula (1)

[Chemical 5] (In the formula, R represents a hydrogen atom, a halogen atom, a nitro group, a lower alkyl group or a lower alkoxy group) [hereinafter, sometimes referred to as "compound (1)" or "present active ingredient"]. ] Is contained as an active ingredient, The Alzheimer's disease therapeutic agent characterized by the above-mentioned is provided.

The group R defined in the above general formula (1)
Examples thereof include a hydrogen atom, a halogen atom, a nitro group, a lower alkyl group or a lower alkoxy group. Examples of halogen atoms include chlorine atom, bromine atom, fluorine atom,
Examples include iodine atoms. A lower alkyl group has 1 carbon atom
To 4 linear or branched alkyl groups, including, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl group, sec-butyl, tert-butyl group, etc., preferably methyl, tert- A butyl group and the like. The lower alkoxy group means a linear or branched alkyl group having 1 to 4 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a sec-butoxy group, and a tert-butoxy group. However, a methoxy group is preferable.

The compound (1) used in the present invention includes some known compounds, but most of them are novel compounds themselves and can be produced, for example, by the following method. That is, equation (2)

[Chemical 6] 5-nitro-2-aminothiazole represented by
[Compound (2)] is present in the reaction solvent in the presence of a base,
General formula (3)

[Chemical 7] (In the formula, X represents a reactive functional group which is eliminated by reacting with an amino group, and R has the same meaning as described above), and is represented by a sulfonyl compound (hereinafter, referred to as “compound (3)”). Compound (1) can be produced by reacting.

The reactive functional group which reacts with and leaves the amino group defined by the group X in the general formula (3) means that it reacts with the amino group of the compound (2) to form --NHSO _2-. And a known sulfonyl chloride compound. As a suitable example of such a compound (3), a corresponding sulfonyl chloride compound can be mentioned.

The reaction solvent used in the above reaction is, for example, N, N-dimethylformamide (DM
A solvent which is inert to the reaction of F), dimethyl sulfoxide, dichloromethane, tetrahydrofuran or the like can be mentioned, but tetrahydrofuran is a preferable example.

Examples of the base used in the above reaction include inorganic bases such as potassium carbonate, sodium carbonate, calcium carbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium hydride, potassium hydride and sodium amide. , Sodium methylate, t-
Alcoholates such as butoxypotassium, and known tertiary organic amines such as triethylamine, diisopropylethylamine and pyridine are mentioned, and sodium hydride is a preferred example. The amount of the above base used is usually
A molar ratio of 1 to 1.1 times that of the compound (2) is suitable.

The above reaction may be carried out usually at room temperature, and the reaction time may be determined by thin layer chromatography (TL).
C), high performance liquid chromatography (HPLC), etc., it is possible to wait until compound (1) is maximally produced and then terminate the reaction as appropriate, but it is usually from several hours to over ten hours. It is a degree.

The compound (1) thus obtained is collected from the reaction solution by appropriately combining extraction, washing, concentration, calm chromatography, crystallization and the like. If further purification is required, column chromatography using a carrier such as silica gel, recrystallization using methanol, acetone, ethyl acetate, tetrahydrofuran, etc. as an easy solvent, hexane, etc. as a difficult solvent, and other known purification methods. It can be purified.

Since the compound (1), which is the active ingredient, was intraperitoneally administered to mice at 200 mg / kg, no death was observed. Therefore, the compound (1) is a drug that can be used as a drug. is there.

When the present active ingredient is used as a therapeutic agent for Alzheimer's disease involving β-amyloid protein, the present active ingredient is usually formulated and then administered orally or parenterally such as injection including infusion. The dose depends on the route of administration,
Although it varies depending on the age, weight, symptom and the like of the recipient, generally, it may be about 10-100 mg / kg per adult.

Examples of dosage forms for the above-mentioned formulation include injections, tablets, pills, powders, granules, capsules, etc. Various acceptable pharmaceutical carriers and the like can be used. For example, in the preparation of oral preparations such as tablets, granules and capsules, starch, lactose, sucrose, mannitol, carboxymethyl cellulose, corn starch, excipients such as inorganic salts, methyl cellulose, sodium carboxymethyl cellulose, hydroxypropyl cellulose , Crystalline cellulose, ethyl cellulose, polyvinylpyrrolidone, binder such as macrogol, starch, hydroxypropyl starch, carboxymethyl cellulose,
Disintegrators such as sodium carboxymethyl cellulose and hydroxypropyl cellulose, surfactants such as sodium lauryl sulfate, soybean lecithin, sucrose fatty acid ester and polysorbate 80, fluidity enhancers, and flavoring agents can be used. Further, the drug of the present invention can be used as an emulsion, a syrup, and an elixir.

For preparing parenteral agents such as injections and infusions, generally, distilled water for injection, physiological saline, aqueous glucose solution, vegetable oil for injection, propylene glycol, polyethylene glycol and the like are used as diluents. You can Furthermore, if necessary, a bactericide, a preservative, a stabilizer,
An isotonicity agent, a soothing agent and the like may be added.

[0024]

The effect of reducing the neuronal toxicity induced by the β-amyloid protein of the present active ingredient will be described below. 1. Activity measurement method The cerebral cortex and hippocampus extracted from the rat fetal brain (E18) were cut into small pieces, and then nerve cells were dissociated by trypsin treatment. Modified N2 medium (Bottenstain and Sat) developed by Bottenstein and Sato
o, G. H: Proc. natl. Acad. Sci.
USA. 76, 514-517, 1979) and 0.67 μg / ml vitamin 12.810 μg / ml.
Glucose, 73 μg / ml glutamine, 50 μg / m
In a serum-free medium of a 1: 1 mixture of Dulbecco's modified medium supplemented with 1-gentamicin and Hams F12 medium,
Culture was performed under the conditions of 5% CO ₂ and 37 ° C.

The cells were placed in a 96-well microtest plate.
5 × 10 ⁴ cells were added to each well and cultured for 6 days. On the 6th day, β-amyloid protein (1-
42-residue peptide) was added at 23.8 μM. The drug is
It was dissolved in 0.08% DMSO at the maximum, and β-amyloid protein was co-administered to the culture system at various concentrations. MTTassay (Mosma developed by Mosman on the 9th day
nn, T.N. : J. Immunol. Methods, 6
5 (p. 55, 1983), the inhibitory rate (%) of the drug against the decrease in MTTassay value induced by β-amyloid protein was calculated, and the drug was evaluated using this.

Inhibition rate = [(β protein + MTT of drug addition group
(assay value)-(MTTassay of β protein addition group)
Value)] / [MTTassay value of non-addition group-MTTassay value of β-protein addition group] The inhibitory rate at drug concentrations of 10 ^-4 M and 10 ^-5 M is (-) 25% or more and 50% or more, respectively. Less than (+), 50% or more and less than 100% (++), 100%
The above was expressed as (++++) to show the activity.

2) Measurement results Table 1 shows the measurement results. The indication of the present active ingredient used as a test drug is indicated by the compound number described in Examples below.

[Table 1]

As is clear from the above results, the present active ingredient reduces neuronal toxicity induced by β-amyloid protein, which is a main component of senile plaques accumulated in the brain of Alzheimer's disease, thereby It is useful as a therapeutic agent for Alzheimer's disease, since it suppresses the degeneration and dropout of Alzheimer's disease and prevents the dementia associated with Alzheimer's disease.

[0029]

EXAMPLES Next, the present invention will be described in more detail with reference to production examples and formulation examples of the compound (1) which is the present active ingredient.
The nuclear magnetic resonance spectrum ( ¹
H-NMR) data are shown in Tables 2 and 3 below.

[0030]

Example 1 Synthesis of 4-chloro-N- (5-nitro-2-thiazolyl) benzenesulfonamide (Compound 41) 2 g of 2-amino-5-nitrothiazole (20.7 mmol) was added to anhydrous tetrahydrofuran under an argon atmosphere. 5
It was dissolved in 0 ml, and the reaction system was cooled with ice to give sodium hydride 4
76 mg (20.7 mmol) was added, and the mixture was stirred at room temperature for 30 minutes. 4-chlorobenzenesulfonyl chloride 4.37 dissolved in 10 ml of anhydrous tetrahydrofuran was added thereto.
g (20.7 mmol) was added dropwise, and the mixture was stirred at room temperature overnight. After a small amount of ice water was added to stop the reaction, the solvent was distilled off under reduced pressure, water was added, and the mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the obtained residue was washed with ethyl acetate and a small amount of methanol.
The obtained crude product was reprecipitated with methanol, ethyl acetate and tetrahydrofuran-hexane to give the title compound 1.2.
5 g (3.90 mmol, yield 18.8%) was obtained.

[0031]

Example 2 Synthesis of N- (5-nitro-2-thiazolyl) benzenesulfonamide (Compound 140) Substituting benzenesulfonyl chloride for 4-chlorobenzenesulfonyl chloride in Example 1 yielded the title compound. Obtained at 26.0%.

[0032]

Example 3 Synthesis of 4- (t-butyl) -N- (5-nitro-2-thiazolyl) benzenesulfonamide (Compound 50) 2-amino-5-nitrothiazole 1 g (6.89 mmol) under an argon atmosphere. ) Is anhydrous tetrahydrofuran 5
Dissolve in 0 ml, cool the reaction system with ice and sodium hydride 1
65 mg (6.89 mmol) was added, and the mixture was stirred at room temperature for 30 minutes. To this, 1.6 g (6.89 mmol) of 4- (t-butyl) benzenesulfonyl chloride dissolved in 10 ml of anhydrous tetrahydrofuran was added dropwise, and the mixture was stirred overnight at room temperature. After quenching with a small amount of ice water, the solvent was distilled off under reduced pressure, water was added, and the mixture was extracted with ethyl acetate. The organic layer was washed with water and 1N hydrochloric acid, dried over anhydrous sodium sulfate, and the crude product obtained by distilling off the solvent under reduced pressure was subjected to silica gel column chromatography (Merck, Art 9385).
And the title compound 40 mg (0.12 mmol,
Yield 2.9%) was obtained.

[0033]

Example 4 Synthesis of 4-Fluoro-N- (5-nitro-2-thiazolyl) benzenesulfonamide (Compound 53) In Example 3, 4-fluorobenzenesulfonyl chloride was used instead of 4-iodobenzenesulfonyl chloride. The title compound was obtained with a yield of 30.4%.

[0034]

Example 5 Synthesis of 4-nitro-N- (5-nitro-2-thiazolyl) benzenesulfonamide (Compound 52) In Example 3, 4-nitrobenzenesulfonyl chloride was used in place of 4-iodobenzenesulfonyl chloride. The title compound was obtained in a yield of 25.9%.

[0035]

Example 6 Synthesis of 4-methoxy-N- (5-nitro-2-thiazolyl) benzenesulfonamide (Compound 59) In Example 3, 4-methoxybenzenesulfonyl chloride was used in place of 4-iodobenzenesulfonyl chloride. After column purification, the product was reprecipitated with a system of methanol and ethyl acetate-hexane to give the title compound in a yield of 9.
Obtained at 0%.

[0036]

Example 7 Synthesis of 4-Methyl-N- (5-nitro-2-thiazolyl) benzenesulfonamide (Compound 44) Sodium hydride 99 mg (4.1
3 mmol) was suspended in 50 ml of anhydrous tetrahydrofuran, the reaction system was ice-cooled, and 500 mg (3.44 mmol) of 2-amino-5-nitrothiazole was added to the reaction system at room temperature for 30 minutes.
Stir for minutes. 4-Methylbenzenesulfonyl chloride 85 dissolved in 10 ml of anhydrous tetrahydrofuran
2 mg (4.13 mmol) was added dropwise and the mixture was stirred at room temperature overnight. After stopping the reaction with a small amount of ice water, the solvent was distilled off under reduced pressure, water was added, and the mixture was extracted with ethyl acetate. Water organic layer,
Wash with 1N hydrochloric acid, dry over anhydrous sodium sulfate, evaporate the solvent under reduced pressure, and wash the resulting crude product with methanol.
220 mg (0.77 mmol, dry) of the title compound
Yield 22.4%) was obtained.

[0037]

Example 8 Synthesis of 4-chloro-N- (1-fluorenyl) benzenesulfonamide (Compound 38) 1-Aminofluorene 300 mg (1.66 mmol)
Was dissolved in 50 ml of anhydrous pyridine, a tetrahydrofuran solution of 348 g (1.83 mmol) of 4-chlorobenzenesulfonyl chloride was added dropwise, and the mixture was stirred at room temperature overnight. The solvent was evaporated under reduced pressure, water and ethyl acetate were added for extraction, the organic layer was washed with 1N hydrochloric acid, and dried over anhydrous sodium sulfate. The solvent was concentrated under reduced pressure, and the obtained crude product was subjected to silica gel column chromatography (Merck, A
rt9385, hexane: ethyl acetate = 5: 1) and then recrystallized from hexane-ethyl acetate to give the title compound (146 mg, 0.41 mmol, yield 24.7%).
Got

[0038]

Example 9 Preparation of Capsules 4-Chloro-N- (5-nitro-2-thiazolyl) benzenesulfonamide (Compound 41) dried in a vacuum desiccator and ground in a bee bag was each packed in a capsule filling machine. 0
No. capsules were filled to obtain capsules containing 250 mg of the active ingredient.

[0039]

[Table 2]

[0040]

[Table 3]

Claims (1)

[Claims] 1. A general formula (1): (In the formula, R represents a hydrogen atom, a halogen atom, a nitro group, a lower alkyl group or a lower alkoxy group), as an active ingredient, a therapeutic agent for Alzheimer's disease.